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Digital Imaging (digital + imaging)
Terms modified by Digital Imaging Selected AbstractsDigital Imaging: A Promising Tool for Mushroom IdentificationACADEMIC EMERGENCY MEDICINE, Issue 7 2003Connie B. Fischbein BA Mushroom poisoning is a diagnostic and treatment dilemma for health care professionals. Decisions regarding treatment following ingestions are usually made without a firm identification of the fungus and tend to be more aggressive than necessary. The identification of mushrooms is beyond the scope of health care professionals, and a mycologist is essential to make an accurate identification. Telemedicine and digital imaging is an emerging technology that can assist in mushroom identification and facilitate patient care. The efficacy of using digital images sent over the Internet was tested in a pilot project. This article describes three cases in which digital images and verbal descriptions assisted in mushroom identification. When the actual specimen was sent to a mycologist, a definitive identification was obtained and compared with the presumptive identification. Digital images alone do not permit definitive identification; however, they often contain sufficient information to help the clinician rule out the possibility of a severely toxic species. Data accumulated to date indicate that digital imaging can be an important tool in the diagnosis and treatment of mushroom ingestion, and possibly other biologicals such as plants, insects, and reptiles. [source] Integration of Digital Imaging into Emergency Medicine EducationACADEMIC EMERGENCY MEDICINE, Issue 1 2002Lisa Chan MD No abstract is available for this article. [source] A comparative evaluation of digital imaging, retinal photography and optometrist examination in screening for diabetic retinopathyDIABETIC MEDICINE, Issue 7 2003J. A. Olson Abstract Aims To compare the respective performances of digital retinal imaging, fundus photography and slit-lamp biomicroscopy performed by trained optometrists, in screening for diabetic retinopathy. To assess the potential contribution of automated digital image analysis to a screening programme. Methods A group of 586 patients recruited from a diabetic clinic underwent three or four mydriatic screening methods for retinal examination. The respective performances of digital imaging (n = 586; graded manually), colour slides (n = 586; graded manually), and slit-lamp examination by specially trained optometrists (n = 485), were evaluated against a reference standard of slit-lamp biomicroscopy by ophthalmologists with a special interest in medical retina. The performance of automated grading of the digital images by computer was also assessed. Results Slit-lamp examination by optometrists for referable diabetic retinopathy achieved a sensitivity of 73% (52,88) and a specificity of 90% (87,93). Using two-field imaging, manual grading of red-free digital images achieved a sensitivity of 93% (82,98) and a specificity of 87% (84,90), and for colour slides, a sensitivity of 96% (87,100) and a specificity of 89% (86,91). Almost identical results were achieved for both methods with single macular field imaging. Digital imaging had a lower technical failure rate (4.4% of patients) than colour slide photography (11.9%). Applying an automated grading protocol to the digital images detected any retinopathy, with a sensitivity of 83% (77,89) and a specificity of 71% (66,75) and diabetic macular oedema with a sensitivity of 76% (53,92) and a specificity of 85% (82,88). Conclusions Both manual grading methods produced similar results whether using a one- or two-field protocol. Technical failures rates, and hence need for recall, were lower with digital imaging. One-field grading of fundus photographs appeared to be as effective as two-field. The optometrists achieved the lowest sensitivities but reported no technical failures. Automated grading of retinal images can improve efficiency of resource utilization in diabetic retinopathy screening. Diabet. Med. 20, 528,534 (2003) [source] Digital imaging and public engagement in palaeontologyGEOLOGY TODAY, Issue 4 2009Karl T. Bates Public engagement and the promotion of science to a wider non-academic audience form an integral role of the professional scientist in the twenty-first century. The high level of public interest in palaeontology means that the Earth's prehistoric past can provide an important medium through which to communicate information concerning contemporary scientific issues. Here we explain how modern computer techniques can be used to enhance public understanding of complex palaeontological issues. [source] Digital imaging in transmission electron microscopyJOURNAL OF MICROSCOPY, Issue 1 2000G. Y. Fan The digital revolution currently under way, as evidenced by the rapid development of the Internet and the world-wide-web technologies, is undoubtedly impacting the field of transmission electron microscopy (TEM). Digital imaging systems based on charge-coupled device (CCD) technologies, with pixel array size up to 2 k × 2 k at the present and increasing, are available for TEM applications and offer many attractions. Is it time to phase out film cameras on TEMs and close the darkrooms for good? This paper reviews digital imaging technologies for TEM at different voltages, and contrasts the performance of digital imaging systems with that of TEM film. The performance characteristics of CCD-based digital imaging systems, as well as methods for assessing them, are discussed. Other approaches to digital imaging are also briefly reviewed. [source] Digital photography for patient counseling in dermatology , a studyJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 11 2008F Kaliyadan Abstract Objectives To evaluate the use of digital photography in dermatology as an aid to patient counseling and follow-up. Materials and methods Two hundred patients attending the dermatology Out-Patient Department at our centre over a 1-year period were included. Half the group, randomly assigned (G1), had their clinical photographs taken and were counseled using basic imaging software, their images and other relevant images regarding their disease and possible treatment outcomes. The control group (G0) was counseled without using any kind of imaging. Patient satisfaction was scored in both groups after the initial counseling session and then after 2 months. Results The test group (G1) gave statistically significant higher scores at both readings compared with the control group (G0). Conclusion Digital imaging can be a very effective tool for the dermatologist for patient counseling. [source] Fred Hollows lecture: Digital screening for eye diseaseCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 3 2000Ij Constable ABSTRACT The purpose of this study was to explore progress, in the adaptation to community screening for blinding eye disease, of digital imaging devices and technology for storage and transmission. Available imaging systems were compared to gold standard clinical photography in terms of sensitivity and specificity for diagnosis of common blinding eye conditions. Since the use of expensive non-portable imaging devices is likely to be limited for widespread community screening purposes, a portable fundus camera (Nidek, Chiyoda-ku, Japan) and a prototype monocular digital indirect ophthalmoscope constructed at the Lions Eye Institute (LEI) were selected for comparative trials for the screening of optic disc cupping, glaucoma and clinical signs of diabetic retinopathy. Fifty-one eyes of 27 consecutive patients being assessed at the LEI clinic for glaucoma were dilated and photographed with a Zeiss retinal camera, and digital images were taken with the portable Nidek NM100 fundus camera (Carl Zeiss, Oberkochen, Germany) or with a prototype digital monocular indirect ophthalmoscope. Vertical cup : disc ratios (VCDR) were measured on the disc photographs by one ophthalmologist while three other clinicians were presented with compressed digital images in random order to estimate VCDR. Field trials were also carried out to demonstrate the practicality of compression, local storage and then transmission by mobile telephone ISDN lines and satellite, of optic discs and fundus images of patients with diabetes in either rural Western Australia or Surabaya, Indonesia. Kappa values of correlations of measurement of agreement between measured and estimated VCDR were 0.87, 0.45 and 0.84, respectively, for the three observers, corresponding to a specificity of 79,97% and a sensitivity of 70,95%. The portable Nidek fundus camera was also assessed for specificity and sensitivity in the diagnosis of diabetic retinopathy in comparison to standard Zeiss fundus camera photographs. Of 49 eyes in 25 consecutive patients attending the LEI clinic for assessment of diabetic retinopathy, three ophthalmologists assessed photographs and images in random order. When used for screening diabetic retinopathy, the digital images of the Nidek camera were graded as adequate quality in only 56% of eyes compared to 93% of the photographs. The kappa value of agreement in analysis of diabetic retinopathy was only 0.30. The prototype digital monocular indirect ophthalmoscope compared favourably with the Nidek camera. At 1:5 compression, images of size 36 kB transmitted from Surabaya to Perth took 29 s on the mobile telephone, while uncompressed images took 170 s. Images compressed 1:5 were transmitted in 60 s using the satellite telephone, while the uncompressed images took 240 s. Satellite transmission was more expensive but the lines were more stable than telephone connections from Indonesia. Digital imaging is becoming a powerful tool for ophthalmology in clinical records, teaching and research, and interoffice diagnostic opinions. It also has enormous potential for community screening for blinding eye diseases, such as glaucoma and diabetic retinopathy. Inexpensive portable imaging devices that are easy to use, and on which local health workers might be trained, must be developed and validated in terms of sensitivity and specificity of performance. The technology of image capture, image compression, transmission, data base storage and analysis is rapidly evolving and becoming less expensive. [source] A comparative evaluation of digital imaging, retinal photography and optometrist examination in screening for diabetic retinopathyDIABETIC MEDICINE, Issue 7 2003J. A. Olson Abstract Aims To compare the respective performances of digital retinal imaging, fundus photography and slit-lamp biomicroscopy performed by trained optometrists, in screening for diabetic retinopathy. To assess the potential contribution of automated digital image analysis to a screening programme. Methods A group of 586 patients recruited from a diabetic clinic underwent three or four mydriatic screening methods for retinal examination. The respective performances of digital imaging (n = 586; graded manually), colour slides (n = 586; graded manually), and slit-lamp examination by specially trained optometrists (n = 485), were evaluated against a reference standard of slit-lamp biomicroscopy by ophthalmologists with a special interest in medical retina. The performance of automated grading of the digital images by computer was also assessed. Results Slit-lamp examination by optometrists for referable diabetic retinopathy achieved a sensitivity of 73% (52,88) and a specificity of 90% (87,93). Using two-field imaging, manual grading of red-free digital images achieved a sensitivity of 93% (82,98) and a specificity of 87% (84,90), and for colour slides, a sensitivity of 96% (87,100) and a specificity of 89% (86,91). Almost identical results were achieved for both methods with single macular field imaging. Digital imaging had a lower technical failure rate (4.4% of patients) than colour slide photography (11.9%). Applying an automated grading protocol to the digital images detected any retinopathy, with a sensitivity of 83% (77,89) and a specificity of 71% (66,75) and diabetic macular oedema with a sensitivity of 76% (53,92) and a specificity of 85% (82,88). Conclusions Both manual grading methods produced similar results whether using a one- or two-field protocol. Technical failures rates, and hence need for recall, were lower with digital imaging. One-field grading of fundus photographs appeared to be as effective as two-field. The optometrists achieved the lowest sensitivities but reported no technical failures. Automated grading of retinal images can improve efficiency of resource utilization in diabetic retinopathy screening. Diabet. Med. 20, 528,534 (2003) [source] Adolescent Foley Catheter Technique for Visualizing Hymenal Injuries in Adolescent Sexual AssaultACADEMIC EMERGENCY MEDICINE, Issue 9 2003Jeffrey S. Jones MD Abstract Objectives: To determine the usefulness of the Foley catheter balloon technique for visualizing injuries of the estrogenized hymen in adolescent sexual assault victims compared with supine labial traction. Methods: A prospective clinical trial of 20 adolescent (age 13,16 years old) victims of sexual assault evaluated at a free-standing Nurse Examiner Clinic was conducted over a four-month study period. The clinic, affiliated with an emergency medicine residency program, is staffed by registered nurses who have been specially trained to perform medicolegal examinations using colposcopy with digital imaging. The Foley catheter technique uses an inflated balloon in the distal vaginal vault to expand the estrogenized hymen to its full capacity so that the edge may be readily visualized for signs of trauma. The Foley technique was compared with gross inspection, using supine labial traction, to photodocument hymenal abnormalities. Photographs of the hymen were obtained using the labial traction technique and then with the Foley technique. Three emergency physicians independently examined each pair of photographs with high interrater agreement for the presence of injury (,= 0.88). Results: Twenty adolescent sexual assault victims volunteered for the study; mean age was 14.8 years. Gross inspection of the hymen using supine labial traction identified hymenal injuries in three patients (15%). Use of the Foley catheter balloon technique allowed identification of hymenal abnormalities in nine additional cases (60%). The common injuries to the hymen included lacerations (30%), followed by ecchymosis and abrasions. One patient (5%) voiced discomfort (mild pressure sensation) during inflation of the balloon. Conclusions: The Foley catheter balloon technique is a simple method allowing improved photodocumentation of hymenal trauma in adolescent sexual assault victims compared with supine labial traction. [source] Digital Imaging: A Promising Tool for Mushroom IdentificationACADEMIC EMERGENCY MEDICINE, Issue 7 2003Connie B. Fischbein BA Mushroom poisoning is a diagnostic and treatment dilemma for health care professionals. Decisions regarding treatment following ingestions are usually made without a firm identification of the fungus and tend to be more aggressive than necessary. The identification of mushrooms is beyond the scope of health care professionals, and a mycologist is essential to make an accurate identification. Telemedicine and digital imaging is an emerging technology that can assist in mushroom identification and facilitate patient care. The efficacy of using digital images sent over the Internet was tested in a pilot project. This article describes three cases in which digital images and verbal descriptions assisted in mushroom identification. When the actual specimen was sent to a mycologist, a definitive identification was obtained and compared with the presumptive identification. Digital images alone do not permit definitive identification; however, they often contain sufficient information to help the clinician rule out the possibility of a severely toxic species. Data accumulated to date indicate that digital imaging can be an important tool in the diagnosis and treatment of mushroom ingestion, and possibly other biologicals such as plants, insects, and reptiles. [source] Identification of root canals in molars by tuned-aperture computed tomographyINTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2000R. Nance Abstract Aim To compare the tuned-aperture computed tomography system of imaging to conventional D-speed film for their ability to identify root canals in extracted human molars. Methodology Thirteen maxillary and six mandibular human molars were mounted in acrylic blocks to simulate clinical conditions by surrounding the teeth with a radiodense structure. The teeth were then imaged with conventional D-speed film using a standard paralleling technique, and with a modified orthopantomograph OP100 machine using a Schick no. 2 size CCD sensor as the image receptor. The source images were registered and TACT slices were generated using TACT WorkbenchÔ Software. Three observers were asked to identify the number of canals in the conventional film group and the TACT image group using specific criteria. Ground truth was established by cross-sectioning the teeth at the coronal, middle, and apical thirds of the roots and directly visualizing the root canal morphology. Results TACT imaging detected 36% of 4th canals in maxillary molars and 80% of third canals in mandibular molars. Conventional film detected 0% of fourth canals in maxillary molars and 0% of third canals in mandibular molars. The differences in canal detection between the two techniques were statistically significant (Wilcoxon matched pair sign rank test, P = 0.001). Conclusions In this study, the TACT system of digital imaging was superior to conventional film in the detection of root canals in human molars and may be useful for the detection of root canals that will probably be missed upon conventional X-ray examination. [source] Holographic digital Fourier microscopy for selective imaging of biological tissueINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 6 2004Sergey A. Alexandrov Abstract We present an application of digital Fourier holography for selective imaging of scatterers with different sizes in turbid media such as biological tissues. A combination of Fourier holography and high-resolution digital recording, digital Fourier microscopy (DFM) permits crucial flexibility in applying filtering to highlight scatterers of interest in the tissue. The high-resolution digital hologram is a result of the collation of Fourier holographic frames to form a large-size composite hologram. It is expected that DFM has an improved signal-to-noise ratio as compared to conventional direct digital imaging, e.g., phase microscopy, as applied to imaging of small-size objects. The demonstration of the Fourier filtering capacity of DFM using a biological phantom represents the main focus of this article. © 2005 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 14, 253,258, 2004; Published online inWiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.20031 [source] Health disparities in the forensic sexual assault examination related to skin colorJOURNAL OF FORENSIC NURSING, Issue 4 2009FAAN, Marilyn S. Sommers PhD Abstract Little is known about the role of skin color in the forensic sexual assault examination. The purpose of this study was to determine whether anogenital injury prevalence and frequency vary by skin color in women after consensual sexual intercourse. The sample consisted of 120 healthy (63 Black, 57 White) women who underwent a forensic sexual assault examination following consensual sexual intercourse. Experienced sexual assault forensic examiners using visual inspection, colposcopy technique with digital imaging, and toluidine blue application documented the number, type, and location of anogenital injuries. Although 55% of the total sample was observed to have at least one anogenital injury of any type following consensual intercourse, the percentages significantly differed for White (68%) and Black (43%) participants (p= 0.02). When the presence of anogenital injury was analyzed by specific anatomical region, a significant difference between White and Black participants was only evident for the external genitalia (White = 56%, Black = 24%, p= .003), but not for the internal genitalia (White = 28%, Black = 19%, p= .20) or anus (White = 9%, Black = 10%, p= 0.99). A one standard deviation-unit increase in L* values (lightness) was related to a 150% to 250% increase in the odds of external genitalia injury prevalence (p < 0.001). While Black and White participants had a significantly different genital injury prevalence, dark skin color rather than race was a strong predictor for decreased injury prevalence. Sexual assault forensic examiners, therefore, may not be able to detect injury in women with dark skin as readily as women with light skin, leading to health disparities for women with dark skin. [source] Introduction of picture archiving and communication system at The Townsville HospitalJOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 4 2005PE Jackson Summary The performance of a medical imaging department (MID) can be judged by the timing and availability of an image and its report to the treating physician, as this can impact on the patient's treatment, as well as the length and cost of a patient's hospitalization. The use of digital imaging has dramatically improved report turnaround time. In October 2001, The Townsville Hospital (TTH) was opened as a 460 bed greenfield site and as part of the installation a picture archiving and communication system, including web distribution of images and reports to wards and clinics, was included. This retrospective analysis of the MID at TTH is the first data on departmental productivity and individual workload and how these have changed since the hospital's opening 2 years ago, with some ideas for further improvement. [source] Digital imaging in transmission electron microscopyJOURNAL OF MICROSCOPY, Issue 1 2000G. Y. Fan The digital revolution currently under way, as evidenced by the rapid development of the Internet and the world-wide-web technologies, is undoubtedly impacting the field of transmission electron microscopy (TEM). Digital imaging systems based on charge-coupled device (CCD) technologies, with pixel array size up to 2 k × 2 k at the present and increasing, are available for TEM applications and offer many attractions. Is it time to phase out film cameras on TEMs and close the darkrooms for good? This paper reviews digital imaging technologies for TEM at different voltages, and contrasts the performance of digital imaging systems with that of TEM film. The performance characteristics of CCD-based digital imaging systems, as well as methods for assessing them, are discussed. Other approaches to digital imaging are also briefly reviewed. [source] The use of digital imaging in the restoration of missing dental tissues with a removable implant prosthesisJOURNAL OF PROSTHODONTICS, Issue 4 2002Edward M. Amet DDS [source] Metastable Phase Formation from an Undercooled Rare-Earth Orthoferrite MeltJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2002Kosuke Nagashio High-speed digital imaging was conducted during the containerless solidification of rare-earth orthoferrites (RE = La, Sm, Dy, Y, Yb, and Lu) with the perovskite structure to determine the metastable phase and elucidate its growth behavior. Observation using a high-speed video camera revealed that the formation of the metastable phase became pronounced, and double recalescence from the metastable phase to a stable phase occurred, as the ionic radius of the rare-earth element decreased. In the present paper, the formation of the metastable phase is discussed systematically in view of the stability of the perovskite structure and the activation energy of nucleation. [source] Digital image analysis of the flagellar beat of activated and hyperactivated suncus spermatozoaMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 4 2007Takane Kaneko Abstract The flagellar beat of hyperactivated Suncus spermatozoa was analyzed by digital imaging and was compared to that of the nonhyperactivated (activated) spermatozoa in order to examine the function of the accessory fibers during the flagellar beat and the sliding filament mechanism inducing the motility of the hyperactivated spermatozoa. Unusual large and long characteristics of the accessory fibers were involved in generating the gently curved bends and a low beat frequency. Examination of the motility parameters of the flagellar beat of the activated and hyperactivated spermatozoa attached to a slide glass by their heads revealed that there were two beating modes: a frequency-curvature dependent mode in the activated flagellar beat and a nearly constant frequency mode in the hyperactivated flagellar beat. The hyperactivated flagellar beat was characterized by sharp bends in the proximal midpiece and a low beat frequency. The sharp bends in the proximal midpiece were induced by the increase in the total length of the microtubule sliding at the flagellar base. The rate of microtubule sliding (sliding velocity) in the axoneme remained almost constant in the flagellar beat of both the activated and hyperactivated spermatozoa. Comparison of the sliding velocity in Suncus, golden hamster, monkey, and sea urchin sperm flagella with their stiffness suggests that the sliding velocity is determined by the stiffness at the flagellar base and that the same sliding microtubule system functions in both mammalian and echinoderm spermatozoa. Mol. Reprod. Dev. 74: 478,485, 2007. © 2006 Wiley-Liss, Inc. [source] Exploring the third dimension in root resorptionORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 2 2004EKM Chan Structured Abstract Authors , Chan EKM, Darendeliler MA Objective , To review and investigate the validity of various 2D quantitative measurement techniques, and to explore the third dimension of root resorption. Design , A review of the literature involving various quantitative evaluation of root resorption. Results , Quantitative evaluation of resorption using radiographs has proven to be highly inaccurate because of magnification errors and their inability to be readily repeated and reproduced. Studies using histology sections of samples have proven to be laborious and technique sensitive. Inherent parallax errors and loss of material in data transfer have denied the true understanding of this 3D event. Conclusion , With the evolution in computing technology and digital imaging, the vision of evaluating the extent of root resorption in 3D has materialized. It was demonstrated that 3D volumetric quantitative evaluation of root resorption craters was feasible and its accuracy and repeatability was high. [source] Is digital retinal imaging alone sufficient as a screening tool for diabetic retinopathy?PRACTICAL DIABETES INTERNATIONAL (INCORPORATING CARDIABETES), Issue 8 2002Endocrinology, FM Razvi Specialist Registrar Diabetes Abstract Aims. To determine whether the addition of direct ophthalmoscopy to digital retinal imaging confers an advantage over imaging alone. Method. Cohort study in a DGH teaching hospital, Birmingham. Two hundred diabetic patients attending eye-screening clinics were examined by digital retinal imaging and ophthalmoscopy. Results. In 115 (57.5%) patients the quality of the image was sufficient and no additional information was gained from also carrying out ophthalmoscopy. In a total of 76, representing 38% of patients examined, the addition of ophthalmoscopy improved detection of diabetic retinopathy. Conclusion. There is an advantage in combining digital imaging and ophthalmoscopy in eye screening, as opposed to using either method individually, to improve the detection of diabetic retinopathy. Copyright © 2002 John Wiley & Sons, Ltd. [source] The impact of anterior cruciate ligament injury on lubricin metabolism and the effect of inhibiting tumor necrosis factor , on chondroprotection in an animal modelARTHRITIS & RHEUMATISM, Issue 10 2009K. A. Elsaid Objective To examine the effects of anterior cruciate ligament transection (ACLT) in a rat model on lubricin metabolism and its relationship to markers of inflammation and cartilage damage, and to determine whether blocking the metabolic effects of tumor necrosis factor , (TNF,) by etanercept increases the chondroprotection provided by lubricin. Methods Unilateral ACLT was performed in Lewis rats. Levels of lubricin, TNF,, interleukin-1, (IL-1,), and sulfated glycosaminoglycans (sGAG) in synovial fluid (SF) lavage specimens and synovial tissue lubricin gene expression were evaluated at 1 week and 4 weeks following ACLT. Histologic evaluation of articular cartilage included staining with lubricin-specific monoclonal antibody 9G3 and Safranin O. The percentage of lubricin staining on the surface of articular cartilage in weight-bearing areas was estimated by digital imaging. Blocking of TNF, was performed using etanercept, which was administered subcutaneously at a dose of 0.5 mg/kg around the ACL-transected joints, using different dosing strategies. The ACL-transected and contralateral joints of these rats were harvested 4 weeks following surgery. Results Four weeks following ACLT, SF lubricin concentrations and the percentage of cartilage surface lubricin staining were significantly lower in the injured joints compared with the contralateral joints. A significant decrease in synovial tissue lubricin gene expression was associated with elevated TNF, and IL-1, concentrations in SF lavage samples. With all of the etanercept treatment strategies, blocking of TNF, significantly increased the amount of lubricin bound to cartilage, coupled with a significant decrease in sGAG release. However, changes in the concentrations of lubricin in SF were variable. Conclusion Blocking TNF, resulted in a chondroprotective effect, exemplified by increased lubricin deposition on articular cartilage and a decrease in sGAG release from articular cartilage in an animal model of posttraumatic arthritis. [source] Photoscreening for diabetic retinopathy: a comparison of image quality between film photography and digital imagingCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 4 2004Christina MC Klais MD Abstract Purpose:,Retinal images from patients attending an urban screening centre before and after the transition from film photography to digital image acquisition were analysed for quality of image. Methods:,A total of 1946 diabetic patients, aged 12,92 years (mean 55.6 ± 14.88 years), were included in this retrospective study of retinal screening techniques. Each imaging group was subdivided into age-matched groups. In all subjects pupils were pharmacologically dilated before photography. The images were reviewed by the same three experienced observers and graded at the time of screening from grade 1 (excellent quality) to grade 4 (unreadable). Results:,Of 938 patients in the film group, 31.3% had excellent images, 38.2% good, 22.7% poor and 7.8% were unreadable. Of the 1008 patients in the digital imaging group, 25.3% had excellent images, 46.3% good, 14.6% poor and 13.8% were unreadable. A significant difference was observed in patients over 65 years of age who exhibited a threefold increase in failure rate with digital imaging (33.7% v 11.3%)(P < 0.0001). Conclusion:,In this study population a statistically significant degradation of image quality was observed in those older than 65 years following transition to digital photography. This has implications for service provision planning. [source] |